Meridional transport of ozone in the lower stratosphere

Informations projet

METRO

N° de convention de subvention: ENV4970520

Projet clôturé

Date de début 1 Janvier 1998

Date de fin 30 Juin 2000

Financé au titre de

• Specific programme of research and technological development in the field of environment and climate, 1994-1998

Coût total

Aucune donnée

Contribution de l’UE

Aucune donnée

Coordonné par

CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE
France

CORDIS fournit des liens vers les livrables publics et les publications des projets HORIZON.

Les liens vers les livrables et les publications des projets du 7e PC, ainsi que les liens vers certains types de résultats spécifiques tels que les jeux de données et les logiciels, sont récupérés dynamiquement sur OpenAIRE .

Livrables

Transport and mixing of chemical constituents in the stratosphere

A European network of ground-based ozone lidars, wind radars and ozonesondes was activated (during the winters of 1997/98 to 1999/2000, in the frame of THESEO and THESEO 2000 campaigns), each time meteorological forecast indicated the pass above one of the stations of the network of an air mass coming from the Arctic or from the subtropics. In complement, an airborne ozone lidar allowed to study in detail some air transport events. A set of high-resolution transport models allowed the activation of the ground-based networks and to plan airborne lidar flights in order to interpret the results. The approach followed during METRO-THESEO, improved our understanding of the role of filamentation processes in the mixing of stratospheric air between Polar Regions, mid-latitudes and sub-tropics. The METRO-THESEO ground based network of lidars/radars/radiosondes, as well as the airborne ozone lidar, were successfully activated on alerts for the study of polar filaments and sub-tropical intrusions. The comparison between observations and simulations made with high-resolution transport models on isentropic surfaces was very satisfactory, indicating that such models are well adapted to predict the presence of ozone laminae due to polar filaments and subtropical intrusions. The mechanisms of formation of filaments under the action of large scale Rossby wave, are now well understood and simulated. Preliminary studies were made to better understand the mechanisms of mixing of such filaments under the action of small scale processes and to quantify the contribution of meridional transport to the stratospheric ozone budget at mid-latitude. However, there is still some work to do in this direction.